core: extended to send slots list stride for stride
slave: changed to receive slots list stride by stride
core needs to send slot update on request

A slot update used to be sent when the core was resetting on request
for the chat channel.  With not resetting the core, the slot update
wasn´t sent anymore.
fixed an inconsistency in slots list management
slave: facialEnable has been replaced by stFACE_ENABLE
slave: stop is not a global variable anymore
fixed: sitting agents were misplaced to an unexpected sitting position
slave: unsit agents that did not give permission to animate

       recomposed doSeats() to clean up convoluted inlined code
slave: some more less convoluted code, and PS: doSeats() also checks
       whether the agent to be moved and rotated is sitting or not
slave: sanitizing facials: position and rotate agents first, then do
       		  	   something about their faces

This makes seating a lot faster.
slotupdates:  Instead of having to send the full list, a single slot
	      can be sent in a slot update.

Adjusters are now working, but not repositioning the sitter.  Probably
doSeats() needs to be called to position the sitter every time the
slot is updated (i. e. every time the adjuster is moved, and when
adjusting is stopped).

The core has a bug or glitch in that it somehow ties the seat a sitter
is put into to the slot number rather than to the seat number.  This
means that when an adjuster is used and the slot number the seat is in
changes due to updating the slot (i. e. seat gets a different stride
in the slots list), the sitter may be put into an unexpected seat when
they sit again.

Besides, adjusting has the problem that on every switch of a pose, the
notecard is read again and the adjustment gets overwritten.  This
makes adjusting even more awkward than it genuinely is anyway.

Memory consumption needs to be fixed.